Add return type to function to avoid eslint warning explicit-module-boundary-types

I'm using strict typescript and I want all functions to explicitly define their return types.
However, when generating the types using code generator, the function have no return type.

Of course I can disabled eslint for the file (/* eslint-disable @typescript-eslint/explicit-module-boundary-types */), but this is messy

Example ;
```
export function useFindRefBudgetEntityQuery(
baseOptions?: Apollo.QueryHookOptions<
FindRefBudgetEntityQuery,
FindRefBudgetEntityQueryVariables
>
) {
return Apollo.useQuery<
FindRefBudgetEntityQuery,
FindRefBudgetEntityQueryVariables
>(FindRefBudgetEntityDocument, baseOptions);
}
```

the returnType is compiled but not set to this function
```
export type FindRefBudgetEntityQueryResult = Apollo.QueryResult<
FindRefBudgetEntityQuery,
FindRefBudgetEntityQueryVariables
>;
```

adding it works fine

```
export function useFindRefBudgetEntityQuery(
baseOptions?: Apollo.QueryHookOptions<
FindRefBudgetEntityQuery,
FindRefBudgetEntityQueryVariables
>
):Apollo.QueryResult<
FindRefBudgetEntityQuery,
FindRefBudgetEntityQueryVariables
> {
return Apollo.useQuery<
FindRefBudgetEntityQuery,
FindRefBudgetEntityQueryVariables
>(FindRefBudgetEntityDocument, baseOptions);
}

```